Program takes header of a http response and hash with SHA-256 hashing function: If http response field is const (e.g. Server: nginx) then hash whole line, if not, just leave the field name.
It creates a fingerprint of a http server.
Host: github.com
Connection: close
User-Agent:
Accept-Encoding: gzip
Accept-Charset: ISO-8859-1,UTF-8;q=0.7,*;q=0.7
Cache-Control: no-cache
Accept-Language: de,en;q=0.7,en-us;q=0.3
Referer:
Then it removes all spaces and creates the hash